1. Field of the Invention
The present invention relates to communication devices for communicating signals wirelessly.
Especially, the present invention relates to a system and method for transmitting digital data between communicating devices using acoustic tones as the information carriers for the data.
2. General Background
One of the most difficult challenges faced by providers of low cost wireless computer peripheral devices is the need to distribute custom interface hardware so that the peripheral device can communicate with the computer. The interface hardware not only adds cost to the product, but for many products such as low cost toys, the sales and distribution channels are not prepared to support the distribution of these additional computer devices.
As a result, a mechanism is required whereby devices can communicate with a personal computer, or with each other, using standard hardware (e.g., digital signal processing chips, analog to digital converters, etc.). In addition, the devices, employing this communication mechanism, should be flexibly designed to operate in conditions where line-of-sight communication between said devices is required.
There are many techniques that encode data into an audio frequency signal for transmission and subsequent detection over a communications channel. These techniques as a class are fundamentally different in that they do not use the acoustic medium (air or another material) pressure waves as the communications mechanism.